The data processing device (10) has an input unit, a data input interface for communication with an assigned measuring device, and a memory unit for storing the data sets emitted by the input unit or received by the data input interface. A computer unit and a data output interface (22) is provided and adjusted such that a user activate a selection of data sets from the data sets stored in the memory unit by the input unit. Independent claims are also included for the following: (1) a method for operating the data processing device for processing measured values of a blood sugar measuring device (2) a computer program with a program code.